[20.06] Red Snowballs on the Ragged Edge of the Solar System

W. Romanishin (U. of Oklahoma), S. C. Tegler (Northern Arizona Univ.)

We have obtained B-V and V-R colors for a sample of 17
centaurs and Kuiper belt objects (KBOs) using the Keck II
telescope. Combined with our previously reported colors, we
now have a sample of about 30 objects for which we have
measured optical broadband colors. Our previous sample
showed objects split into gray and red groups, with no hint
of any correlation of color with any orbital parameter or
other physical property. With the enlarged sample, we find
that classical KBOs with perihelion distances greater than
40 AU, particularly those with low orbital inclination, are
extraordinarily red.

We wish to acknowledge funding from the NASA Planetary
Astronomy Program, and also access to the Keck Observatory
through NASA.